7 Raw, partly machined and finish-machined materials namely, polytetafluoroethylene, tin, bronze, copper, and steel for plain bearings of plastics and metal as semi-finished products, namely, washers, thrust washers, bearings, plain bearings, bushings, plain bushings, flanged bushings, strips and sliding bearings and elements for machines and engines; elements of plain bearings of the above mentioned plain bearing materials as finished products namely, washers, thrust washers, bearings, plain bearings, bushings, plain bushings, flanged bushings, strips and sliding bearings for use in machines and engines